2024 No Indoor air quality in the primary school of China—results from CIEHS 2018 study https://www.sciencedirect.com/science/article/abs/pii/S0269749121016766?via%3Dihub Zhu, Yuan-duo Asia Review Elementary (K-5) Carbon Dioxide (CO2) Carbon Monoxide (CO) Particulate Matter (PM) Volatile Organic Compounds (VOCs) Bacteria Fungi Indoor air quality Multi-center Exposure School China In a nationwide study of 66 classrooms in China, over half exceeded PM2.5 and PM10 guidelines. Pollutant levels correlated with inadequate ventilation. Findings underscore the urgent need to improve IAQ to protect student health. 2021